As a record number of 4.92 lakh Olive Ridley turtles have crawled to the Rushikulya coast in Odisha, scientists have tagged more than 6,000 turtles to gather more information about their breeding behaviour and migration.
“On the Day 6 of arribada on the Rushikulya coast, we have recorded 4.92 lakh nests and are still counting. This is the highest nesting which has broken all records for the coast,” said Divisional Forest Officer, Berhampur, Amlan Nayak.
During the nesting period scientists of the Zoological Survey of India (ZSI) have tagged more than one per cent of turtles that have arrived on the beach. “The more turtles we tag the more information we will have about the breeding behaviour and re-migration interval,” scientist at the ZSI, Basudev Tripathi, said. He said the possibility of tag returns was very low and last year, when 1,200 turtles were tagged, there were only four tag returns.
Ministry’s statement
On March 30, the Ministry of Environment, Forest, and Climate Change (MOEFCC) took note of both spectacular nesting at the Rushikulya rookery and the tagging of turtles. “The ZSI team is monitoring the nesting population, counting the arribada throughout the night since 26th March 2022… Around 1,200 turtles tagged every night, in the last three nights, more than 4,000 female turtles have been tagged by #ZSI,” the MOEFCC had said in a series of tweets. Arribada is a Spanish word meaning “arrival by sea” and refers to the mass nesting behaviour exhibited by Kemp’s Ridley and Olive Ridley sea turtles.
Scientists of the ZSI explained how decades of tagging yielded interesting insights about the Olive Ridley turtles.
Travel up to Sri Lanka
“Before the tagging of the turtles, the information we had was that it was a migratory species. Now the tagging has revealed that the Olive Ridley turtles can travel up to Sri Lanka. Also, we came to know that the migratory turtle is present in the entire Bay of Bengal and even on the coast of Andhra Pradesh and Tamil Nadu,” Dr. Tripathi said.
There are two mass nesting sites for Olive Ridley turtles in Odisha — the Gahirmatha Marine Sanctuary and the Rushikulya coast — and the tag returns of the turtles have pointed at “inter-rookery movement” of these turtles.
“Earlier it was considered that there are two different sets of population of the Olive Ridleys, one at Gahirmatha and the other at Rushikulya and during migration, the turtles return to the same coast. But the tag returns have confirmed that a turtle which has nested at Gahirmatha can return later at Rushikulya and vice versa,” the scientist added. Commenting on the conservation implication of the inter-rookery movement, Director of the ZSI, Dhriti Banerjee, emphasised on “equal protection for both the nesting sites at Gahirmatha and Rushikulya”.
Olive Ridley turtles are protected under the Wild Life (Protection) Act, 1972, as a Schedule I species and are categorised as Vulnerable as per the IUCN Red List.
